1. Field
The present disclosure relates generally to accessing satellites and, in particular, to exchanging information with satellites. Still more particularly, the present disclosure relates to a method and apparatus for sending information from a satellite to a ground station.
2. Background
Satellites may be natural or artificial satellites. A natural satellite is a naturally occurring object in orbit, such as the moon. An artificial satellite is a satellite placed into orbit by human operators. The use of the term “satellite” in this disclosure refers to artificial satellites and not natural satellites.
Satellites are placed into orbit for different purposes. For example, a satellite may be used to collect information, transmit information, or perform other types of operations. More specifically, a satellite may be used to collect information about the surface of the Earth, oceans, weather conditions, and other types of information. Satellites also may be used to facilitate communications.
Satellites typically include computer-controlled systems. A satellite often includes a host and a payload. The host may include systems that control the satellite. These systems perform tasks, such as power generation and control, thermal control, telemetry, attitude control, orbit control, and other suitable operations.
The payload provides functions to users of the satellite. The payload may include antennas, cameras, and other suitable devices. For example, with respect to communications, the payload in a satellite may be used to provide Internet access, telephone communications, radio, television, imagery, and other types of communications.
The payload of the satellite may be used by different entities. For example, the payload may be used by the owner of the satellite, one or more customers, or some combination thereof.
For example, the owner of a satellite may lease different portions of the payload to different customers. In one example, one group of antennas on the satellite may be leased to one customer, while a second group of antennas may be leased to a second customer.
When satellites are shared by different customers, each customer may have a separate communications link and controller on the satellite. The controller allows the particular customer to control operation of the antenna and the associated communications capability of the antenna that is leased to the customer.
Leasing a satellite to multiple customers may increase the revenues that an owner of a satellite can obtain. Further, a customer may use a subset of the total resources in a satellite for a cost that is less than the cost for the customer to purchase and operate a satellite, to build and operate a satellite, or to lease an entire satellite.
The additional controllers and other hardware that allow for the end-user customers' control of a portion of a satellite's capability may increase the cost for the satellite. Further, these components also may increase the weight of the satellite by an amount that is more than desired.
Therefore, it would be desirable to have a method and apparatus that takes into account at least some of the issues discussed above as well as possibly other issues.